From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from cthulhu.engr.sgi.com (cthulhu.engr.sgi.com [192.26.80.2]) by neteng.engr.sgi.com (980427.SGI.8.8.8/970903.SGI.AUTOCF) via ESMTP id DAA92851 for ; Tue, 6 Apr 1999 03:43:13 -0700 (PDT) Return-Path: Received: (from majordomo-owner@localhost) by cthulhu.engr.sgi.com (980427.SGI.8.8.8/970903.SGI.AUTOCF) id DAA21594 for linux-list; Tue, 6 Apr 1999 03:41:46 -0700 (PDT) mail_from (owner-linux@relay.engr.sgi.com) Received: from sgi.com (sgi.engr.sgi.com [192.26.80.37]) by cthulhu.engr.sgi.com (980427.SGI.8.8.8/970903.SGI.AUTOCF) via ESMTP id DAA91336 for ; Tue, 6 Apr 1999 03:41:44 -0700 (PDT) mail_from (ulfc@bun.falkenberg.se) Received: from bun.falkenberg.se (dialup87-3-7.swipnet.se [130.244.87.39]) by sgi.com (980327.SGI.8.8.8-aspam/980304.SGI-aspam: SGI does not authorize the use of its proprietary systems or networks for unsolicited or bulk email from the Internet.) via ESMTP id DAA07094 for ; Tue, 6 Apr 1999 03:41:42 -0700 (PDT) mail_from (ulfc@bun.falkenberg.se) Received: (from ulfc@localhost) by bun.falkenberg.se (8.8.7/8.8.7) id MAA25320 for linux@cthulhu.engr.sgi.com; Tue, 6 Apr 1999 12:31:35 -0400 Date: Tue, 6 Apr 1999 12:31:35 -0400 From: Ulf Carlsson To: Linux SGI Subject: HAL2 spec bug Message-ID: <19990406123135.A21186@bun.falkenberg.se> Mail-Followup-To: Linux SGI Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.95.4i Sender: owner-linux@cthulhu.engr.sgi.com Precedence: bulk The DMA noise problem was actually a specification bug. I should not configure cfgdma as a 16 bit device as the specification explicitly tells me to do. If it's configured for 16 bit DMA transfers are the low 8 bits just dumped or replaced with a noise if they differ from the upper 8 bits. It's kind of hard to write a decent driver when the spec lies for me.. - Ulf